The new technologies of High-order Multi-Input Multi-Output (MIMO), multi-cell cooperative transmission, etc., will be adopted in a 3GPP Long Term Evolution (LTE)-Advanced system, i.e., the advancement of an LTE system, which is an evolved system of a third-generation mobile communication system, to improve the performance of the system.
Dedicated pilots are adopted in the LTE-A system to demodulate data in order to better support the new technologies. A dedicated pilot corresponds to a data stream, and pilots keep orthogonal between respective streams. In a transmission scheme with rank1 and rank2, orthogonality between pilots of the two streams is ensured in the Code Division Multiplexing (CDM) mode; in a transmission scheme with rank3 and rank4, orthogonality between pilots of the four streams is ensured in hybrid of Frequency Division Multiplexing (FDM) and CDM mode; and in a transmission scheme with rank5, rank6, rank7 and rank8, orthogonality between pilots of the eight streams is ensured in hybrid of FDM and CDM mode. As can be apparent, the CDM mode is involved for the pilots in all the transmission schemes. When Walsh codes or a normalized Walsh codes are adopted as pilots in the CDM mode, the power sum of pilots over one Orthogonal Frequency Division Multiplexing (OFDM) symbol may differ from that over another so that the power of one OFDM symbol may differ from that of another.